The present invention relates to insulated gate field effect transistors and, more particularly, to insulated gate field effect transistors of the normally off type. There exists a need both for high frequency (greater than one Gigabit) integrated circuit logic and microwave and millimeter wave analog circuitry. Attempts to fabricate devices which will operate at the higher frequencies using, for example, GaAs have succeeded in the case of normally on, "depletion mode" field effect transistors, but no successful (wide dynamics range, i.e., .gtorsim.2 volt) normally off device has been fabricated.